Best BTC prototype production

Ersa supports its customers more than ever today in processes involving the production of prototypes or functional samples. Ersa rework systems have made a name for themselves as ideal assistants for development departments, in particular in the field of “Bottom Terminated Components” (BTC). The soldering of seemingly simple designs such as MLF (Micro Lead Frame) or QFN (Quad Flat No Lead) can quickly become a large obstacle during the completion of sample assemblies. With these components, the right quantity of solder paste must be applied – this is just as critical for a good soldering result as the even heating of the soldering spots. One method that has proved its worth in practice both for sample equipping and for repairs is the printing of solder paste on the component using a precisely dimensioned template, followed by placement and soldering. The Ersa Dip&Print Station serves well during component printing. The component is fixed precisely in a recess in the template, printed on the underside with solder paste and then lifted out of the template. Then the printed component is further processed.

In the case of the Ersa rework systems HR 550 and HR 500, the component is aligned to the lands on the board with the aid of a beam splitter lens and then set in place by a motor-driven unit. Component sizes from 50 x 50 mm (HR 500) or 70 x 70 mm (HR 550) are possible. Thanks to an additional zoom lens, the HR 550 can even place tiniest chips up to the 01005 design. Here, “01” stands for the length and “005” for the width of the component in the unit inch/100. The strengths of the two systems really come into play when components with a large number of connections and tight contact spacing have to be placed precisely. They are indispensable for BGA (Ball Grid Arrays) and QFP (Quad Flat Packs) in particular. For near-series soldering processes the assembly is pre-heated from below in accordance with the preselected soldering profile, and the component soldered in place during a sensor-guided soldering process. All the soldering points receive the same quantity of heat and the assembly only experiences the temperature necessary for safe soldering. Customers who would like to make use of automated equipping and soldering processes during the prototyping phase can process SMD components down to size 01005 reliably using the Ersa HR 600/3P.

Thanks to their hybrid heating technology, Ersa rework systems are even suitable for soldering several components in one process. With small assemblies, such as those used in the field of sensor systems, all soldering points can even be generated in one process – sometimes over several boards in the panel, providing the maximum process area of 70 x 70 mm is not exceeded. The Ersa systems use extremely homogeneous infrared systems from below to ensure the boards are preheated evenly. The hybrid heater heads also stand out due to their very balanced heat transfer. They do not need any component-specific nozzles in the soldering process. Suitable profile settings enable many components to be soldered, right through to a completely equipped board. The controlling of temperature by means of a thermal element on the top of the board makes a controlled and safe process possible even at the first attempt. It has been shown in practice that the quality of the soldering spots is comparable with the series standard.
The open system design of the hybrid rework systems permits additional process checks with the aid of a reflow process camera. This provides high-resolution images during solder melting, thus reducing the thermal load to the minimum necessary.

The product portfolio of Ersa GmbH contains further equipment for the ideal processing of sample assemblies: For gentle manual soldering work the i-CON VARIO 4 provides four soldering tools that can be used at the same time plus an optional pre-heating plate – contact soldering with the i-TOOL or the 250 W power pack POWER-TOOL, hot air soldering with the i-TOOL AIR S, THT desoldering with the X-TOOL VARIO and the SMD desoldering tweezers CHIP TOOL. The rework station HR 100 is a good choice for pure soldering work at components up to 20 x 20 mm edge length. The HR 200 rework system is suitable for components up to 30 x 30 mm.